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Why is moving on the Moon more than just weighing less?

A crate weighs less on the Moon, but its mass does not vanish. Lifting it and changing its horizontal motion ask different things of a person or machine, so lower gravity does not make every task effortless.

3–7 min

Questions you could explore

  • What changes in an ideal lift, and what stays the same in an ideal horizontal push?
  • Why does an object's mass remain relevant on the Moon even though its weight is smaller?

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Space

A crescent Moon is not a partly switched-off Moon

Sunlight illuminates half the Moon, while its changing position around Earth changes how much of that lit half we can see. A phase is different from an eclipse, where one body blocks light from reaching another.

3–5 min
Space

Two eclipses, two different shadows

A solar eclipse and a lunar eclipse both involve the Sun, Earth, and Moon, but the shadow falls in a different place. In one, the Moon’s shadow reaches Earth; in the other, the Moon moves into Earth’s shadow. The Moon’s tilted orbit helps explain why these alignments do not happen every month.

5–7 min
Space

What can century-old photographs reveal about stars today?

A star photographed on a glass plate a century ago can become a new measurement when compared with later observations. Harvard's DASCH project digitizes an astronomical plate archive, alongside dates and logbooks. Explore how calibration makes those old images useful for investigating changes across decades.

8–10 min
Why is moving on the Moon more than just weighing less? | Speech Topic | speaking.app